Peptidomic insights into gluten peptide degradation: Exploring bacterial strains as a palliative strategy for celiac disease

Wheat gluten peptides from the gliadin protein produce an immune response in patients with celiac disease. This research aims to identify potential gliadin epitope degrading bacterial strains for celiac disease treatment. The immunogenic gluten peptides hydrolyzing capacity of 29 Generally Recognized As Safe (GRAS) bacterial strains was evaluated. Among these strains, 21 showed the capacity to hydrolyze gliadin previously digested with pepsin and trypsin by means of a glutenase activity assay. Furthermore, all of these were able to grow in a minimal gliadin medium. The principal component analysis (PCA) and the peptide molecular weight profile study suggested that the Bacillus strains belonging to the species Bacillus subtilis , Bacillus siamensis , and Bacillus amyloquefaciens , along with one of the strains of the genus Corynebacterium glutamicum evaluated, achieved a high degradation of gluten peptides. The peptidome sequencing of the culture media with digested glutenin fermented by the strains with high potential to hydrolyze gluten peptides revealed a reduction of 16% to 50% in the most problematic peptides compared to the control. These findings provide valuable insights into the potential of broad-spectrum bacterial strains to reduce the immunogenic and toxicity of gluten proteins. • Gliadin peptides trigger immune responses in celiac disease patients. • From all isolates 21 evidenced glutenase activity in the assay. • Bacillus spp. and Corynebacterium glutamicum showed high gluten degradation. • Peptidome analysis revealed a 16–50% reduction in toxic gluten peptides. • Promising future use of this bacteria as probiotics for celiac disease